December 24th and December 25th stood out because they were the wettest days of the month which in turn evolved into the most hydrologically active period across the region. S.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS SJU wrote it up.
December 24th and December 25th stood out because they were the wettest days of the month which in turn evolved into the most hydrologically active period across the region. By the evening of December 24th, a Flood Watch was issued for most of Puerto Rico and the U.S. Virgin Islands as heavy rain began to envelope the area due to shower and thunderstorm development from the interaction of local effects and a low pressure center northeast of Hispaniola that was slowly drifting east northeast across the forecast area. Maximum rainfall reports from this event ranged from 5 to 9 inches. The two highest reports in Puerto Rico were 7.13 inches in San Lorenzo and 9.0 inches in Aibonito. The runoff from this rainfall resulted in flash flooding in Aibonito, Fajardo, Las Piedras and Naguabo. Rapid and significant rises were also noted on the Rio Fajardo, Rio Naguabo, Rio Gurabo, Rio de La Plata and the Rio Grande de Loiza and many of its tributaries.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS San Juan, PR wrote its last area forecast discussion before the first event at Dec 24, 2:58 PM AST, 2 hours 2 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JUAN PR
258 PM AST THU DEC 24 2009
.SYNOPSIS...A LOW PRESSURE SYSTEM NORTHEAST OF HISPANIOLA WILL
CONTINUE TO TRACK EASTWARD. VARIABLY CLOUDY SKIES...WITH
OCCASIONAL SHOWERS...ARE EXPECTED FOR CHRISTMAS DAY AND THE
UPCOMING WEEKEND...AS THIS LOW PASSES JUST NORTH OF THE LOCAL
ISLANDS AND THE REMNANTS OF AN OLD FRONTAL BOUNDARY PUSH SOUTHWARD
ACROSS THE REGION.
&&
.DISCUSSION...ISOLATED TO SCATTERED SHOWERS CONTINUE TO AFFECT THE
U.S. VIRGIN ISLANDS AND THE SOUTHEAST PORTIONS OF PUERTO RICO. THE
DOPPLER RADAR IS SHOWING A BAND OF SHOWERS ASSOCIATED TO THE
BEFORE MENTIONED LOW...ALONG THE PUNTA CANA AREA. THIS BAND OF
SHOWERS AND THUNDERSTORMS IS FORECASTED TO MOVE EASTWARD ACROSS
THE MONA PASSAGE AND AFFECT THE WESTERN PORTIONS OF PUERTO RICO
LATE THIS EVENING. SCATTERED TO NUMEROUS SHOWERS ARE EXPECTED TO
SPREAD EASTWARD INCREASING THE POPS FOR MOST OF THE ISLANDS
THROUGH AT LEAST EARLY SATURDAY.
REMNANTS OF AN OLD FRONTAL BOUNDARY TO OUR NORTH IS FORECASTED TO
MOVE SOUTHWARD ACROSS THE LOCAL ISLANDS...BRINGING ANOTHER BRIEF
SURGE IN SHOWER ACTIVITY BETWEEN LATE SATURDAY AND SUNDAY.
&&
.AVIATION...SHORT WAVE OVER THE MONA CHANNEL WILL BRING TSRA
ACTIVITY TO TJBQ AND TJMZ BY 00Z...THEN OVER TJSJ BY 04Z AND THE
USVI SITES 08Z. EXPECT MVFR CIGS WITH TEMPO IFR VSBYS IN +TSRA.
WEAK REMNANT VA OVER THE AREA STILL LINGERING A BIT MAY RESULT IN
SOME HAZY SKIES AROUND FL100...BUT SHOULD HAVE NO IMPACT ON OPS.
&&
.MARINE...THE BUOY 41043 IS ALREADY SHOWING A SIGNIFICANT DECREASE
ON THE SWELL HEIGHT...THEREFORE THE HIGH SURF ADVISORY WILL BE IN
EFFECT THROUGH 6 PM TODAY. ANOTHER NORTHERLY SWELL WILL BE REACHING
OUR LOCAL WATERS ON SUNDAY WITH A LARGE PULSE BETWEEN MONDAY NIGHT
AND TUESDAY. MARINERS AND BEACH GOERS SHOULD MONITOR OUR FORECASTS
AS SMALL CRAFT AND HIGH SURF ADVISORIES WILL BE ISSUED. THERE IS
A POTENTIAL FOR COASTAL FLOODING TO OCCUR THEREFORE COASTAL FLOOD
WATCHES MAY BE ISSUE FOR THE NORTHERN PORTIONS OF THE ISLANDS AND
EXPOSED BEACHES.
&&
.PRELIMINARY POINT TEMPS/POPS...
SJU 75 85 75 83 / 50 50 30 70
STT 76 83 75 84 / 40 40 40 70
&&
.SJU WATCHES/WARNINGS/ADVISORIES...
PR...HIGH SURF ADVISORY UNTIL 6 PM AST THIS EVENING FOR CULEBRA-NORTH
CENTRAL-NORTHEAST-NORTHWEST-SAN JUAN AND VICINITY-VIEQUES.
VI...HIGH SURF ADVISORY UNTIL 6 PM AST THIS EVENING FOR ST.
THOMAS/ST. JOHN/ADJACENT ISLANDS.
&&
93/10HAZARDOUS WEATHER OUTLOOK FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS NATIONAL WEATHER SERVICE SAN JUAN PR 519 AM AST THU DEC 24 2009 AMZ710>745-PRZ001>013-250930- SAN JUAN AND VICINITY-NORTHEAST-SOUTHEAST-EASTERN INTERIOR- NORTH CENTRAL-CENTRAL INTERIOR-PONCE AND VICINITY-NORTHWEST- WESTERN INTERIOR-MAYAGUEZ AND VICINITY-SOUTHWEST-CULEBRA-VIEQUES- THE NEARSHORE AND OFF SHORE ATLANTIC AND CARIBBEAN COASTAL WATERS- 519 AM AST THU DEC 24 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PUERTO RICO AND THE ADJACENT COASTAL WATERS. .DAY ONE...TODAY AND TONIGHT LONG PERIOD...NORTHERLY SWELLS WILL CONTINUE TO AFFECT THE ATLANTIC WATERS AND THE CARIBBEAN PASSAGES THROUGH AT LEAST THIS AFTERNOON. THESE SWELLS WILL CONTINUE TO RESULT IN ROUGH AND HAZARDOUS MARINE AND SURF CONDITIONS...INCLUDING RIP CURRENTS ALONG THE NORTHWEST THROUGH NORTHEAST COASTS OF THE LOCAL ISLANDS. A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR MOST OF THE LOCAL ATLANTIC WATERS AND THE CARIBBEAN PASSAGES. IN ADDITION...A HIGH SURF ADVISORY WAS ISSUED UNTIL 6 PM THIS AFTERNOON FOR BREAKING WAVES 10 TO 15 FEET ALONG SOME NORTHERN COASTS. NO OTHER HAZARDOUS WEATHER IS EXPECTED AT THIS TIME. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY LONG PERIOD...NORTHEASTERLY SWELLS WILL INVADE THE AREA WATERS ON SATURDAY AND LASTING THROUGH THE BEGINNING OF THE UPCOMING WEEK. THESE SWELLS WILL RESULT IN ROUGH AND HAZARDOUS MARINE AND HIGH SURF CONDITIONS...INCLUDING RIP CURRENTS ALONG THE NORTHWEST THROUGH NORTHEAST COASTS OF THE LOCAL ISLANDS. .SPOTTER INFORMATION STATEMENT... SPOTTER REPORTS OF HAZARDOUS SEAS OR DANGEROUS SURF WOULD BE GREATLY APPRECIATED. AMZ715-725-VIZ001-002-250930- ST. THOMAS ST. JOHN ADJACENT ISLANDS-ST CROIX- NEARSHORE ATLANTIC AND ADJACENT CARIBBEAN COASTAL WATERS- 519 AM AST THU DEC 24 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE U.S. VIRGIN ISLANDS AND THE ADJACENT COASTAL WATERS. .DAY ONE...TODAY AND TONIGHT LONG PERIOD...NORTHERLY SWELLS WILL CONTINUE TO AFFECT THE ATLANTIC WATERS AND THE CARIBBEAN PASSAGES THROUGH AT LEAST THIS AFTERNOON. THESE SWELLS WILL CONTINUE TO RESULT IN ROUGH AND HAZARDOUS MARINE AND SURF CONDITIONS...INCLUDING RIP CURRENTS ALONG THE NORTHWEST THROUGH NORTHEAST COASTS OF THE LOCAL ISLANDS. A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR MOST OF THE LOCAL ATLANTIC WATERS AND THE CARIBBEAN PASSAGES. IN ADDITION...A HIGH SURF ADVISORY WAS ISSUED UNTIL 6 PM THIS AFTERNOON FOR BREAKING WAVES 10 TO 15 FEET ALONG SOME NORTHERN COASTS OF SAINT THOMAS...SAINT JOHN AND ADJACENT SMALLER ISLANDS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY LONG PERIOD...NORTHEASTERLY SWELLS WILL INVADE THE AREA WATERS ON SATURDAY AND LASTING THROUGH THE BEGINNING OF THE UPCOMING WEEK. THESE SWELLS WILL RESULT IN ROUGH AND HAZARDOUS MARINE AND HIGH SURF CONDITIONS...INCLUDING RIP CURRENTS ALONG THE NORTHWEST THROUGH NORTHEAST COASTS OF THE LOCAL ISLANDS. .SPOTTER INFORMATION STATEMENT... SPOTTER REPORTS OF HAZARDOUS SEAS OR DANGEROUS SURF WOULD BE GREATLY APPRECIATED.
The national radar mosaic for the moment the first event began.
35 flash flood, 2 debris flow, 1 heavy rain, 1 flood. Local standard time, as filed.
Periods of heavy rain were reported across the municipality of Aibonito. The heavy rains led to flash flooding and landslides.
Roads 173, and 14 Barrio La Plata; 162 at Barrio Cuyon; 718 at Sector Campo Bello, Barrio Pasto; 722 at Barrio Robles; 717 at Barrio Algarrobo; 723 at Pulguillas; 722 at Sector La Sierra Rabanal; 162 at Barrio Pasto and Cuyon; 716 at Barrio Cuyon; 718 Sector Playita Barrio Pasto. Most of these roads experienced landslides, and some were closed to traffic.
A home was reported flooded at Sauce street in Fajardo Gardens.
A home was reported flooded along El Conquistador Avenue, Monte Brisas neighborhood.
A home was reported flooded at San Marcos street, San Pedro neighborhood.
A home was reported flooded along street 4, Baralt neighborhood.
Street flooding was reported along Union street.
A home was reported flooded along marginal road, barrio San Isidra III.
A home was reported flooded along 13 street at Barrio Quebrada Vueltas.
A home was reported flooded along Union street, in Puerto Real.
A flooded home was reported along road 935, Barrio Ceiba Norte, Marin sector.
A car was reported stranded in water in front of Olympic City.
Heavy rains that began on Christmas evening persisted through early Christmas Day. Around 250 families were affected by the rains and floods. The worst hit area was the Aibonito town and the San Luis sector. Many homes close to the river and the town were flooded, as well as Barrios La Plata, Pasto, and Cuyon. Flood water levels rose to around 3 feet in some of the properties. USGS river gauge at Rio de la Plata at Proyecto La Plata rose above flood stage to 18.77 feet. Twenty seven persons were rescued from the flash floods.
A flooded home was reported along Road 173, at La Plata.
A house was reported flooded at Vistas de San Lorenzo sector, Lirio Rd in the municipality of San Lorenzo.
A home was reported flooded by runoff at Lirio Street in Villas de San Lorenzo.
A car was covered by flood waters along road 929 before reaching Barrio Brazo Seco.
A house was flooded at Bo. Toita , rd 14 intersection with Rd 7729, at sector La Merced in the municipality of Cayey.
A home was reported flooded along road 14 at Barrio Toita, Sector La Merced.
A flooded home was reported at the end of Nazareth street in Barriada San Luis.
A flooded home was reported along Domingo Colon street at Barriada San Luis.
A flooded home was reported along Baldorioty street.
Road 31 was reported flooded in Pena Pobre.
A flooded home was reported along Trinitaria street in Brisas de Aibonito.
Jerico street was reported flooded at Barriada San Luis.
Two stranded vehicles and flooding were reported along road 717 in Barrio Pasto.
A flooded home was reported along Matias Soto street in downtown Cayey.
A flooded home was reported along road 14 at Barrio Maton Abajo.
Two flooded homes were reported along the Domingo Colon street in Barrio San Luis.
Road 189 in front of Valle de los Ensuenos was reported flooded.
River was reported out of its banks along road 173 at Barrio Rabanal.
A home was reported flooded along Sardis street at Extension San Luis.
A flooded home was reported along road 789, Las Flores sector, Tomas de Castro II in Caguas.
A flooded home was reported along the Malave sector at Barrio Buena Vista.
A flooded home was reported along Siloe street at Barriada San Luis.
A flooded home was reported along Mileto street at Extension San Luis.
A flooded home was reported along road 7729 In Barrio Toita, Filemon Sector.
A wall of mud and debris at least five feet high crashed into a home at Barrio Arenas, Los Ares sector in Las Piedras municipality, damaging all its contents, and forcing its residents to evacuate and seek shelter in a neighboring home. Twenty four fighting roosters were killed by the mudslide.
Loiza river was reported out of its banks along road 951 at Barrio Las Cuevas. Callejon Salgado and El Ancon street were reported flooded.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Puerto Rico in 2009Every state in 2009This day in weather historyWarnings in Puerto Rico, December 2009
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 209071, 209072, 209596, 209595, 209597, 209598, 209599, 210120, 210119, 210103, 210230, 210239, 209070, 210138, 210094, 210278, 210158, 210095, 210153, 210135, 210133, 210136, 210227, 210096, 210128, 210148, 210172, 210180, 210149, 210229, 210170, 210121, 210280, 210167, 210122, 210126, 210164, 213764, 210224.